Nice, clear bassy sound
I bought this and the Shuguang 12AX7-A for a Valvestate VS100. I ran them both through clean channel with a Russian Big Muff. I instantly felt I had the bassy fuzz that I wanted. After a few days I tried the Shuguang and I was not quite as impressed. I ran it the same way, but there was something off, and it was all very muddy and distorted, in a bad way. So, I changed back to the JJ one day after having played a bit with the Shuguang, and I didn't change/turn anything in terms of knobs, and so I really heard that big difference. Now, the distortion through the JJ through the Valvestate alone is good as well. Though, the same can be said for the Shuguang, probably. I recommend this for a Valvestate VS100.